Difference Between Biome and Ecosystem

Separation of ecosystems and biomes is a problem in terms of space and time. A given ecosystem may vary over time, with ecological succession, stream movements, drought, and extinction of species, introduction of exotic species, human interferences and other factors. Biomes are defined on the basis of key life forms. They are equally dynamic on a longer time scale. The edges of biomes may move with global warming or cooling, changes in rainfall, movement of glaciers, and rising sea level etc. Neither ecosystems nor biomes can be easily marked on a map. In addition, they will never remain unchanged.

What is an Ecosystem?

An ecosystem is a functional unit or a system in the environment where abiotic or nonliving components and biotic or living organisms interact. Abiotic components include soil, water, atmosphere, light, temperature, humidity and pH etc. Soil provides anchorage for all plants. Also, it provides habitat for many organisms. Water is required by all organisms, to perform their metabolic activities. Atmosphere includes carbon dioxide for photosynthesis, oxygen for respiration and nitrogen for nitrogen fixing organisms. Sunlight provides energy for all naturally existing ecosystems. Also, a suitable temperature is necessary for all the metabolic activities. The living organisms have an internal hierarchy within an ecosystem. They are the primary producers, consumers and the decomposers. Living organisms interact with each other forming food chains within an ecosystem. Food chains are linked at certain places forming complex webs. In an ecosystem, these food webs contribute to the existence of an ecosystem; more complex the food webs are, the ecosystems remain stable. Non living substances are also needed by an ecosystem. All materials required by organisms are obtained from the environment. Decomposers play an important role in the cycling process. The main source of energy in an ecosystem is solar radiation. Energy is not cycled, and it moves unidirectionally. The world ecosystems can be separated into two groups. Those are terrestrial ecosystems and the aquatic ecosystems.

What is Biome?

It is a zone on the earth determined by large scale climatic and vegetation characteristics. Biomes are climatically controlled assemblage of organisms. It is the largest geographical biotic unit. Biomes are usually named after the dominant type of life form. For an example, in tropical rain forest, grassland, or coral reef, the dominant life forms are usually plants or corals. A single biome can be widely scattered on earth. Due to similar patterns of natural selection, species in different parts of a biome may be similar in their appearance and behaviors. There are eight major biomes. Those are tundra, taiga, temperate (deciduous) forests, temperate ever greens, tropical rain forest, grassland, desert or tropical deciduous forests. For an example, the grassland biome is characterized by grasses and related species. In this biome, all the plants are adapted to fast, scattered fires, which burn the tops of plants.

What is the difference between Biome and Ecosystem?

• An ecosystem can be large or small. Two similar ecosystems are considered as “two similar ecosystems” rather than “one ecosystem” unless the land in between them is also included.

• In contrast, the word biome is used for visually similar but not necessarily connected areas.

• An ecosystem is generally small when compared to the size of a biome because unlike an ecosystem a biome may be distributed throughout on the entire earth.